Radiation marking of fiber optic cable components

ABSTRACT

A fiber optic cable component, for example, an optical ribbon ( 20,22,24,26 ), individual optical fiber, fiber bundle, or a non-optical fiber component, having a radiation markable section, the radiation markable section including a radiation reactive ingredient compounded with a base matrix material, and methods for creating markings in the radiation markable section. When irradiated with a suitable radiation source, a photochemical reaction occurs that creates markings in the radiation markable section, so that the ribbon classification task may be done with ease and reliability, so that substantial physical damage to the layer by the radiation source is avoided. The marking of fiber optic cable components according to the present invention may, for example, be accomplished by a radiation source of the laser type.

The present invention relates to fiber optic cable components and, moreparticularly, to a fiber optic cable components with markings thereonand methods of making the markings.

Conventional fiber optic cables include optical fiber containingcomponents, for example, optical ribbons or fiber bundles. Opticalfibers conduct light which is used to transmit voice, video, and datainformation. Additionally, fiber optic cables include non-optical fibercontaining components, for example, rods, strength members, tapes, etc.The optical fibers in an optical ribbon or fiber bundle are generallyencased in a matrix coating of an ultraviolet (UV) light curable type.Typically, such a matrix coating is extruded about a group of opticalfibers that have been arranged in an array, and is then cured byirradiation with a UV light source. The cured matrix coating protectsthe optical fibers and generally fixes the alignment of the respectiveoptical fibers in the array.

Optical fibers may be arranged in an array of the optical ribbon type.FIG. 1 shows adjacent optical ribbons 12-1 and 12-2 of a conventionalribbon stack 12. Optical ribbons 12-1,12-2 each include optical fibers15 encased in a matrix coating 19. A craftsman may gain access tooptical ribbons 12-1,12-2 by cutting away portions of a cable to exposeribbon stack 12. Once stack 12 is exposed, the craftsman may desire todistinguish between and classify the ribbons according to, for example,which telecommunications circuit they are to be associated with. Toclassify the ribbons, the craftsman may look for markings which uniquelyidentify the ribbon, for example, a series of alpha-numeric characterswhich define a label or indicia 16. Indicia 16 includes a series ofprinted dots 17 which depict the alpha-numeric characters. Dots 17 aresmall masses of thermal, solvent, or UV curable ink material whichpresent unevenness, e.g., bump-like and/or trough-like (not shown)irregularities on and/or in the surface of matrix coating 19 (FIG. 2).Where ribbons 12-1,12-2 include essentially permanent indicia 16, thecraftsman's ribbon classification task may be done with ease andreliability. It is therefore desirable that indicia 16 be essentiallypermanent, i.e., robust enough to withstand direct abrasion, orprotected by an anti-abrasion overcoating.

Known markings of the printed ink type are printed on the matrix coatingof an optical fiber array, or directly on the optical fibers, but suchmarkings may have disadvantages. U.S. Pat. No. 5,485,539, incorporatedby reference herein, discloses printed ink dots on a matrix coating thatdefine layered dots that form symbols, and a transparent, anti-abrasioncoating may be applied over the printed ink dots. U.S. Pat. No.5,119,464 discloses a process for directly marking optical fibers withink as they move in an array, before being coated with a protectiveenvelope, so that staggered bands of ink are formed on the opticalfibers. Disadvantageously, however, the printed ink type markings may beremoved by a solvent when the ink is on the surface, the print of aribbon or bundle may be transferred to an adjacent ribbon, and/or theprinted ink dots may cause an undesirable level of attenuation loss inthe optical fibers.

Laser marking techniques have been developed to mark fiber optic cablecomponents (e.g., cable jackets), but cause substantial ablation ofportions of the cable jacket. Substantial laser ablation of fiber opticcable components can result in undesirable physical damage of suchcomponents, for example, optical ribbons or bundles. A known lasermarking technique is used to mark optical cable jackets formed of arobust, black polyethylene material suited to the outdoor environment,as disclosed in U.S. Pat. No. 5,049,721, incorporated by referenceherein. Substantial laser ablation causes physical damage in the form ofcraters in the black polyethylene jacket. A colored wax of a contrastingcolor is packed into the craters. The contrasting color wax defines adot matrix of an alpha-numeric configuration; however, thisconfiguration may not be essentially permanent, as the colored wax maybe rubbed off or otherwise become dislodged or flow out of the craters.The physical damage associated with substantial laser ablation of thiskind is not particularly suited for use with optical ribbons or bundles,as the laser would likely punch holes through the optical ribbon anddestroy the optical fibers. Moreover, ablated craters can negativelyaffect the robustness of a thin matrix coating.

Multi-layer cable jackets having laser markable surfaces are expensive,and can be too large for application to optical ribbons, individualoptical fibers, or fiber bundles. A laser marking method for use with afiber optic cable having an outer jacket with inner and outer varnishlayers is disclosed in U.S. Pat. No. 5,111,523, and is incorporated byreference herein. The inner and outer varnish layers require specializedformulations that are applied around the entire circumference of thefiber optic cable jacket. The thickness of the outer layer is greaterthan 5 μm and less than 25 μm, and it is intended to be transformedsuperficially only at the point of laser impact so as to leave a markwhich is darker than the inner varnish layer by virtue of its pigmentbeing transformed. The outer layer may be ablated thereby revealing theinner layer, of a minimum thickness between 15-25 μm, which reflects thelaser radiation. The transformation or ablation can result insubstantial physical damage to the outer varnish layer. Additionally,the two-layer method of marking a fiber optic cable jacket is expensive,and, given size constraints, may not be suitable for application on anoptical fiber ribbon, individual optical fibers, or fiber bundles.

OBJECTS OF THE INVENTION

It is an object of the present invention to provide a fiber optic cablecomponent comprising a radiation markable section including a radiationreactive ingredient, exposure to a radiation source causing a marking tobe made in the radiation markable section so that physical damage to thelayer by the radiation is avoided. The radiation reactive ingredientcan, for example, be selected from the group of photoreactiveingredients consisting of an inorganic compound, a metal salt, aradiation reactive dye, a silver halide material, and a photoreactiveacrylate material.

It is another object of the present invention to provide a method ofmarking a fiber optic cable component, comprising the steps ofirradiating a radiation markable section on a fiber optic cablecomponent with a radiation source and causing a photochemical reactionin the radiation markable section whereby a marking is made in theradiation markable section that contrasts with a color of anothermaterial so that physical damage to the radiation markable section bythe radiation is avoided. The method may utilize a laser as a source ofradiation.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

FIG. 1 is an isometric view of an optical ribbon having conventional inkdots according to the prior art.

FIG. 2 is a cross sectional view of the optical ribbon of FIG. 1 takenat line 2—2.

FIG. 3 is a cross sectional view of a portion of an optical ribbon withmarkings in accordance with the present invention.

FIG. 4 is a cross sectional view of a portion of an optical ribbon withmarkings in accordance with the present invention.

FIG. 5 is a cross sectional view of an optical ribbon with markings inaccordance with the present invention.

FIG. 6 is a cross sectional view of an optical ribbon with markings inaccordance with the present invention.

FIG. 7 is an isometric view of a fiber optic cable incorporating anoptical ribbon with markings in accordance with the present invention.

FIG. 8 is a cross sectional view of a ribbonizing die in accordance withthe present invention.

FIG. 9 is a schematic view of a marking apparatus in accordance with thepresent invention.

FIG. 10 is a schematic view of a marking apparatus in accordance withthe present invention.

FIG. 11 is a schematic view of a marking apparatus in accordance withthe present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to a fiber optic cable component, forexample, an optical ribbon, individual optical fiber, fiber bundle, or anon-optical fiber component, having a radiation markable section, theradiation markable section including a radiation reactive ingredientcompounded with a base matrix material. When irradiated with a suitableradiation source, a photochemical reaction occurs that creates markingsin the radiation markable section, the markings being in color-contrastto adjacent areas, so that the ribbon classification task may be donewith ease and reliability. The photochemically made markings avoid theunevenness of the ink dot type markings of the prior art, and avoidphysical damage to the radiation markable section, so that markinginduced attenuation is minimized and a suitable modulus is preserved.The marking of fiber optic cable components according to the presentinvention may, for example, be accomplished by a radiation source of thelaser type.

With reference to FIGS. 3-6, exemplary fiber optic cable components inthe form of optical ribbons 20,22,24,26 of the present invention will bedescribed. Each of optical ribbons 20,22,24,26 includes a layer 30surrounding optical fibers 21, the fibers preferably include distinctcolor coatings. Layer 30 is a composite matrix that includes a materialsection in the form of a radiation markable section 32, and may includea material section in the form of a transparent or a translucent section38. Radiation markable section 32 includes a radiation reactiveingredient that can be compounded with a base matrix material in a waythat defines a photochemically reactive substance. The radiationreactive ingredient may be, for example, an inorganic compound, a metalsalt, a radiation reactive dye, a silver halide material, and/or aphotoreactive acrylate material.

Layer 30 may be applied to a fiber optic cable component in differentways and may exhibit various colors, shades, tones, etc. afterirradiation. For example, radiation markable section 32 of opticalribbon 20 can be marked with a radiation source to define dots/lines 33(FIG. 3) of a light or faded tone or color. Dots/lines 34 of arelatively darker tone or color may also be made in layer 30, asembodied in optical ribbon 22 (FIG. 4). Layer 30 may be applied over aconventional matrix layer 39 in an optical ribbon 24 (FIG. 5). Inaddition, layer 30 can define a thin layer 36, e.g., a film thicknesslayer, applied on optical ribbon 26 (FIG. 6) that can be marked withdots/lines (not shown). The markings made in layer 30 can be in the formof, for example, alpha-numeric characters, stripes, bands, bar codes,holograms, logos, and/or trademarks.

It may be desirable to incorporate any number of optical ribbons of thepresent invention in a fiber optic cable. Any of optical ribbons20,22,24,26 or combinations thereof may be formed into a stack andincorporated into a fiber optic cable, for example, a fiber optic cable80 (FIG. 7) of the mono-tube type. Fiber optic cable 80 includes, forexample, a stack of optical ribbons 22 with relatively dark markings 34thereon.

As noted above, radiation markable section 32 is a compound of aradiation reactive ingredient and a base matrix material. In addition tobinding optical fibers 21 together, the base matrix material functionsas a color contrasting carrier for the radiation reactive ingredient.The base matrix material preferably is, as noted above, transparent ortranslucent; however, where it is not desired to observe the colorcoatings of the optical fibers, the base matrix material may include anopaque coloring agent. The base matrix material should provide acontrasting background relative to the marking formed after irradiationof layer 30. Additionally, layer 30 preferably has a suitable moduluscharacteristic of 50-1500 mPa, i.e., a modulus that is not overlymodified by compounding the base matrix material with the radiationreactive ingredient. Moreover, the modulus of the base matrix materialshould not be overly modified by controlled radiation dosages associatedwith radiation marking methods of the present invention, describedhereinbelow. Exemplary base matrix materials include radiation curableresins, for example, UV curable resins of the acrylate type, asdisclosed in U.S. Pat. No. 4,900,126, which is incorporated by referenceherein.

As noted above, the radiation reactive ingredient may be any suitablephotoreactive substance that is compatible with the base matrix materialand results in acceptable physical properties, e.g., modulus. Exemplaryradiation reactive ingredients include an inorganic compound and apigment, a metal salt, a radiation reactive dye, a silver halidematerial, or a photoreactive acrylate material. The mixture may be, forexample, mica and a pigment, e.g., titanium dioxide, that is susceptibleto a photochemical reaction in the form of a pigmentation process, orphoto-degradation in the form of ablation, charring, or discoloring.Degradation should not result in substantial physical damage to thedesired properties of the optical ribbon. In addition, the radiationreactive ingredient may be a mixture of carbon black and titaniumdioxide, as disclosed in U.S. Pat. No. 4,959,406, incorporated byreference herein. Other titanium dioxide compounds for laser marking maybe used as well, for example as disclosed in U.S. Pat. No. 5,501,827,incorporated by reference herein.

The radiation reactive ingredient may include a laser beam absorbinginorganic ingredient and a colorant physically bonded to the laserabsorbing inorganic ingredient that is capable of changing color uponbeing irradiated with a laser beam, as disclosed in U.S. Pat. No.5,422,383, incorporated by reference herein. Such suitable inorganicingredients include cordierite, zeolite, zirconium silicate, and calciumsilicate. Suitable colorants include ferri hydroxide, cuprous hydroxide,and other metal containing compounds that are white, black, or blue atroom temperature but change to either a different color or become fadedor colorless upon irradiation with a laser beam.

The radiation reactive ingredient may include a metal salt that issusceptible to photochemical action. For example, the metal saltreaction may be performed by a cuprous salt, or molybdenum oxide, asdisclosed in U.S. Pat. No. 5,053,440 or U.S. Pat. No. 5,489,639, both ofwhich are incorporated by reference herein. Additionally, the radiationreactive ingredient may include a metal salt having a larger meanparticle size than a typical pigment, as disclosed in U.S. Pat. No.5,501,827, incorporated by reference herein. The radiation reactiveingredient can include a metal salt and a fatty acid as disclosed inU.S. Pat. No. 5,300,350, incorporated by reference herein. Suitablefatty acids include stearic acid, palmitic acid, and myrstic acid; andsuitable metal salts are of the zinc, calcium, magnesium, and sodiumtypes.

The radiation reactive ingredient of the present invention can includean azo-dye that is susceptible to photochemical action in the form of adye coloring process. An azo-dye is any of a class of synthetic organicdyes that contain nitrogen as the azo group “-N=N-” as part of theirmolecular structures, as disclosed in U.S. Pat. No. 5,554,196. The basematrix material compounded with an azo-dye forming section 32 can bemarked by means of an UV-laser or IR-laser where the azo-dye comprises adye precursor and a coupler. The dye precursor can be a heterocyclicmono- or bis-arylsulphonylhydrazone, and the coupler may be, forexample, an indole, aniline, pyrazoline or malonitrile, so that afterirradiation with UV-laser light or IR-laser light an azo-dye is formed.

Additionally, the dye coloring process can be performed by a radiationreactive ingredient including an azo-dye having a silver halidephotoreactive material that is photoreactive in the visible (V) lightrange. Suitable silver halide photoreactive materials are disclosed inU.S. Pat. No. 4,207,111, incorporated by reference herein. Formation ofcolor markings can be accomplished by subjecting radiation markablesection 32 having the visible light-reactive silver halide materialtherein to color development by the use of an aromatic primary aminetype developing agent in the presence of a cyan coupler, a magentacoupler, and a yellow coupler. The silver halide particles present inthe exposed color photoreactive material are reduced by the developingagent. An oxidation product of the developing agent reacts by couplingwith the couplers to form a cyan dye, a magenta dye, and a yellow dyerespectively, thereby forming a color marking.

Moreover, the dye coloring process can be performed by a radiationreactive ingredient including a photo-bleachable dye that is responsiveto laser light, as disclosed in U.S. Pat. No. 5,567,207, incorporated byreference herein. Preferably, the laser radiation is controlled so thatphoto-bleaching of the dye occurs without substantially damaging thebase matrix material.

Furthermore, the dye coloring process may be performed by a radiationreactive ingredient including a thermoreactive dye containing as majorconstituents an ordinarily colorless or slightly colored dye precursorand an electron receptive developer. Upon being heated by means of athermal head, thermal pen, or laser beam, the major constituentsinstantly react with each other to form a recorded image in layer 30.Suitable dye precursors and developers are disclosed in U.S. Pat. No.4,742,042, incorporated by reference herein. Use of the dye precursorand developer can result in color images being formed in radiationmarkable section 32.

The dye coloring process may be performed by a radiation reactiveingredient including a fixing dye as disclosed in U.S. Pat. No.5,409,504, which is incorporated herein by reference. The radiationreactive ingredient that is markable by irradiation with UV light may bea fixing dye containing at least one polymerizable double bond, or atleast one polymerizable ring system, and at least one photosensitizer.

Additionally, images can be produced in radiation markable section 32which change their appearance when the viewing angle is changed, asdisclosed in U.S. Pat. No. 4,894,110, which is incorporated by referenceherein, in the form of, for example, a three-dimensional image(hologram). Moreover, radiation markable section 32 may includephotoreactive acrylates, for example, as disclosed in U.S. Pat. Nos.5,395,730 and 4,987,048, incorporated by reference herein film 36.

Manufacture of an optical ribbon, with exemplary reference to a fiberoptic cable component in the form of optical ribbon 20, can beaccomplished by using a ribbonizing die 40 (FIG. 8) adapted forco-extrusion of the radiation markable compound with the matrixmaterial. Ribbonizing die 40 includes an inlet port 42 for receiving theradiation markable compound of markable section 32 under suitabletemperature and pressure conditions, and includes an inlet port 48 forreceiving matrix material 38 under suitable temperature and pressureconditions. The radiation markable compound and matrix material 38 areextruded about an array of optical fibers 21. Next, optical ribbon 20 isfed into to a curing area (not shown) where layer 30 is polymerized.Apparatuses for ribbonizing in general, that are hereby incorporated byreference herein, include: U.S. Pat. Nos. 4,720,165; 4,950,047;5,252,050; and 5,333,233.

A first method of marking a fiber optic cable component, i.e., exemplaryoptical ribbon component 20 prior to or after polymerization of layer30, will now be described with reference to a marking apparatus 50 (FIG.9). Marking apparatus 50 includes a laser controller 51 operativelyassociated with a programmable central processing unit (CPU) 58 and aradiation source, for example, a laser oscillator 52. CPU 58 isprogrammed to control the operating parameters of laser oscillator 52,for example, laser beam scan rate, power density, average power, pulserate and width, and/or repetition rate. Marking apparatus 50 furtherincludes scanning mirrors 54 a,54 b connected to respective motors55,57, which, in turn, are controlled by CPU 58. Marking apparatus 50may include first and second focusing lenses 53,56 for narrowing thelaser beam to a focal point 59. Apparatuses for laser marking ingeneral, incorporated by reference herein include: U.S. Pat. Nos.5,567,207; 4,961,080; 4,874,919; and 4,370,542.

CPU 58 is operative to execute its internal program whereby focal point59 describes the desired characters/pattern to be made on optical ribbon20 as the ribbon continuously moves along a production line. In defininga continuous process, the laser beam scan rate, power density, averagepower, pulse rate and width, and repetition rate are synchronized to theline speed of optical ribbon 20. CPU 58 controls the X-Y position offocal point 59 by adjusting scanning mirrors 54 a,54 b which arecontrolled by motors 55,57. In this way, focal point 59 can be scannedacross ribbon 20 in a continuous or pulsed beam, irradiating layer 30and causing a photochemical reaction that results in the desiredcharacters/patterns.

According to another method of the present invention, a fiber opticcable component, for example, exemplary optical fiber ribbon 22 may bemarked by an image-wise marking apparatus 60 (FIG. 10). Markingapparatus 60 can include a radiation source, for example, a laseroscillator 62 that may be controlled by a CPU and laser controller as inthe embodiment of FIG. 9. Marking apparatus 60 can further include abeam expander 62, a mask 63, and a mirror 64. In operation, the laserbeam emitted by laser oscillator 62 is expanded by beam expander 61. Thelight is shaped by stationary mask 63 into a desired image, and then theimage is reflected by mirror 64 onto radiation markable section 32 ofoptical ribbon 22. The shaped light impinging on layer 32 causes aphotochemical reaction which marks optical ribbon 22 according to thecontours of the image.

Alternatively, a marking apparatus 70 (FIG. 11) including anon-stationary mask 71 may be used to produce an image in a fiber opticcable component, for example, optical ribbon 20. Marking apparatus 70includes a radiation source 72, a rotating mask 71 including a masktemplate 73 with the profile of the image to be marked, and guidepulleys 74. Optical ribbon 20 is continuously fed through apparatus 70and is wrapped at least partially about rotating mask wheel 71. As thisoccurs, radiation source 72 emits light through the profile and intooptical ribbon 20 thereby causing a photochemical reaction resulting inan image 79.

The images made by apparatuses 50,60,70 may depict a pattern/charactersin the form of a registered trademark, e.g., SIECOR®. As noted above,the markings made in layer 30 can be in the form of, for example,alpha-numeric characters, stripes, bands, bar codes (FIG. 9), holograms,and/or logos. Depending on which radiation reactive ingredient is used,the image/lines/dots etc. made by marking apparatuses 50,60,70 may beblack, white, gray, or another color. Marking apparatuses 50,60,70 maybe adapted for use in the marking of fiber optic cable components otherthan optical ribbons, fiber bundles, or individual optical fibers.

In accordance with the present invention, the need to have a sufficientdosage of radiation on radiation markable section 32 to photochemicallycreate a marking therein may be balanced against the need to avoidphysical damage to the optical ribbon (or other fiber optic cablecomponent). In particular, degradation and/or substantial ablation oflayer 30 that can result in, for example, delaminations, solventingress, stress risers, and/or failure sites should be avoided. To avoidphysical damage to layer 30, laser oscillators 52,62 can be of theexcimer, frequency-tripled YAG, copper, or frequency-doubled YAG laseroscillator type, as discussed in U.S. Pat. No. 5,111,523 (incorporatedby reference hereinabove). In general, the radiation dose which strikesthe balance noted above may depend on one or more factors, for example,the controlled operating parameters of the radiation source, thedistance of radiation markable section 32 from the radiation source, thetype and amount of photosensitizer used, and the permeability of thelayer.

The present invention has been described with reference to the foregoingembodiments, which embodiments are intended to be illustrative of thepresent inventive concepts rather than limiting. Persons of ordinaryskill in the art will appreciate that variations and modifications ofthe foregoing embodiments may be made without departing from the scopeof the appended claims. For example, fiber optic cable components in theform of optical fiber arrays of the non-planar type, e.g., optical fiberbundles, can include a radiation markable section 32 according to thepresent invention. Moreover, radiation markable section 32 can beapplied to fiber optic cable components such as, e.g., cores, rods,strength members, tapes, etc. as disclosed in U.S. Ser. Nos. 09/089,201and 09/048,486, which are respectively incorporated by reference herein.Further, radiation markable section 32 may be extended to fullycircumscribe any part of an optical ribbon, bundle, or fiber, or it maybe a longitudinally extruded stripe. Moreover, a release agent, e.g., aTeflon® dry lubricant, can be applied adjacent to radiation markablesection 32, for creating a controlled weak interface or separationlayer. Radiation markable section 32 may be overcoated with a protectivelayer and/or bonded to a substrate with an adhesive. The radiationreactive ingredients may be used singly, or combined in distinctportions of radiation markable section 32, or where compatible, mixedtogether. Radiation markable sections 32 may be included in a fiberoptic cable component using the same or different ingredients. Radiationsources may be sources which emit bands of electromagnetic radiationother than in the IR, UV or V-light ranges. Electron beams may be usedas an alternative to electromagnetic radiation sources.

Accordingly, what is claimed is:
 1. A fiber optic cable component,comprising: a radiation markable section including a radiation reactiveingredient comprising a photoreactive substance selected from the groupof photoreactive ingredients consisting of a silver halide material, aphotoreactive acrylate material or a radiation reactive dye; exposure toa radiation source causing said photoreactive substance to form amarking in said radiation markable section so that substantial physicaldamage to the layer by said radiation is avoided.
 2. The fiber opticcable component of claim 1, said radiation markable section comprising amatrix material.
 3. The fiber optic cable component of claim 1, saidfiber optic cable component comprising an optical fiber array.
 4. Thefiber optic cable component of claim 1, said fiber optic cable componentcomprising an optical fiber.
 5. The fiber optic cable component of claim1, said radiation markable section comprising a base matrix material. 6.The fiber optic cable component of claim 1, said radiation markablesection being disposed on an optical fiber containing component but doesnot surround the component.
 7. The fiber optic cable component of claim6, wherein part of said component not covered by said radiation markablesection includes a clear or translucent matrix material.
 8. The fiberoptic cable component of claim 1, said physical damage includingdelaminations, solvent ingress, stress risers, and/or failure sites. 9.The fiber optic cable of claim 1, wherein said radiation reactiveingredient comprises a thermo-reactive substance.
 10. A fiber opticcable component, comprising: at least one optical fiber; a compositematrix disposed about said optical fiber, said composite matrixcomprising at least two distinct material sections; one of said materialsections comprising a radiation markable section including a radiationreactive dye comprising a photoreactive substance, exposure of saidradiation markable section to a radiation source causing a photochemicalreaction of said photoreactive substance which results in a markingbeing formed in said radiation markable section so that substantialphysical damage to said radiation markable section by said radiation isavoided.
 11. The fiber optic cable component of claim 10, said compositematrix surrounding a plurality of optical fibers.
 12. The fiber opticcable component of claim 10, said composite matrix comprising part of anoptical fiber ribbon.
 13. The fiber optic cable component of claim 10,said at least one optical fiber being observable through one of saidmaterial sections.
 14. The fiber optic cable of claim 10, said radiationreactive dye is selected from the group of dyes consisting of an azo-dyeor a photo-bleachable dye.
 15. The fiber optic cable of claim 10, saidradiation reactive dye further comprising an azo-dye having a silverhalide photoreactive substance.
 16. A fiber optic cable component,comprising: at least one optical fiber; a composite matrix disposedabout said optical fiber, said composite matrix comprising at least twodistinct material sections; one of said material sections comprising aradiation markable section including a radiation reactive ingredientcomprising a photoreactive acrylate substance, exposure of saidradiation markable section to a radiation source causing a photochemicalreaction of said photoreactive substance which results in a markingbeing formed in said radiation markable section so that substantialphysical damage to said radiation markable section by said radiation isavoided.
 17. The fiber optic cable component of claim 16, said compositematrix surrounding a plurality of optical fibers.
 18. The fiber opticcable component of claim 16, said composite matrix comprising part of anoptical fiber ribbon.
 19. The fiber optic cable component of claim 16,said at least one optical fiber being observable through one of saidmaterial sections.